- "The Scourge of the Divine Beast Vah Ruta"
- — In-game title
Waterblight Ganon is a boss in The Legend of Zelda: Breath of the Wild. It is a phantom construct created by Calamity Ganon to corrupt the Divine Beast Vah Ruta, and slay the Zora Champion Mipha. Now, it serves as a boss of the dungeon that the Divine Beast had become within the East Reservoir Lake of the Lanayru region.
Like the other Scourges, Waterblight Ganon is a mass of Malice-flesh and Ancient Sheikah technology arranged in the shape of a crude humanoid torso. Its "face" is a black mask resembling a pair of sideways-pointing horns, with a single blue eye at the center. The mask bears a stubby, thin snout. A long mane of wild red hair runs down its spine, terminating just above the mass of technology that forms its lower body.
Waterblight Ganon has a lanky frame with mismatched arms; the right arm is thin, proportionate to its body, and ends in a hand with five spindly fingers. Its left arm is much longer and bulkier, with the forearm being covered in Ancient Sheikah technology and ending in a device resembling a flattened hammer head. In battle, the device projects a long spear made of blue energy, similar to the blades and heads of other Ancient weapons.
Waterblight Ganon uses its spear and control over water to attack Link. It teleports around fairly frequently to maintain its optimal distance and to protect its eye, which serves as a weak point. Like the rest of the Blights, it is vulnerable to Ancient weapons and the Master Sword; it also takes extra damage from Shock Arrows, especially if hit in the eye.
Initially, Waterblight Ganon mainly attacks with its spear, with a different move depending on Link's distance from it. At long range, it hurls its spear like a javelin, which Link can sidestep fairly easily. At medium range, it stabs its spear in Link's direction or scrapes the tip along the ground in a wide arc. To avoid damage, Link should strafe around the boss as he approaches; if he hears a click or sees the boss's spear sliding forward in its "hand", he should quickly move forward or backward to avoid the sweep attack. If Link is close to the boss, it can stab the ground directly below it with its spear, creating a field of damaging energy that can knock Link off his feet if he does not dodge in time. This attack is well-telegraphed, but it can be hard to see if Link is attacking at melee range; watch for the boss to raise both arms and listen for the faint hum of energy to know when to get back.
After losing half of its health, Waterblight Ganon begins using its elemental powers. It starts the phase by raising the water level in the room, leaving four square platforms to stand on. Since Link is much more vulnerable while swimming, he should only move between platforms when the boss is stunned or teleporting around the room. He can also speed things up by climbing ice pillars summoned with the Cryonis Rune, then gliding to another platform with his Paraglider.
In its second phase, Waterblight Ganon begins hanging upside down in the air, making it harder to hit with melee weapons unless it is stunned first. Although it can still attack with its spear, it can also use Cryonis to summon ice blocks as projectiles. As with the battle against Divine Beast Vah Ruta, Link can counter this attack with either arrows or his own Cryonis, shattering the blocks before they hit him. At low health, Waterblight Ganon starts firing lasers from its eye, similar to a Guardian Stalker. Link can either dodge the beams or bounce them back at the boss with a Perfect Guard, which damages and stuns it for a time.
When Waterblight Ganon's health is depleted, it spews Malice from its body before exploding in a ball of violet light. A Heart Container descends from above as the lingering Malice shielding the core of Vah Ruta disappears, allowing Link to purify the Divine Beast and free Mipha's spirit.
If Link rushes off to Hyrule Castle before freeing Vah Ruta, Waterblight Ganon will appear to fight Link alongside the other undefeated Scourges in a back-to-back boss battle.
Waterblight Ganon was probably specifically designed to have an upper hand against Mipha. It wields a ranged melee weapon, like the Lightscale Trident. It can also use ice powers like Vah Ruta. Whenever it does so, it holds a ball of light blue light in its right hand that aesthetically resembles Mipha's Grace in "Mipha's Touch". It also hovers by the ceiling and can flood the room with water, allowing it to hit Mipha with it is spear whilst not allowing her to retaliate due to a lack of proper range.
Mipha's advice to Link while battling Waterblight Ganon strongly suggests she is speaking from hindsight, giving him information she didn't have during her own battle, which lead to her defeat.